This invention relates to apparatus and methods for making porcelain samples used in selecting external surface characteristics of dental restorations.
In selecting an aesthetically appropriate surface for a specific dental restoration, a shade sample should be very carefully matched to the patient's surrounding teeth. The sample then can be used to obtain a restoration with the appropriate external surface. Such samples are made by firing layers of porcelain powder of precisely known thicknesses to achieve the color hue, value, chroma, and translucence desired. Ordinarily three layers of powder are used. The bottom layer is opaque and the middle and top layer are translucent. The visual qualities of the final shade will depend greatly on the specific thicknesses of the three layers, and those thicknesses must be very carefully controlled.